That also happened to me in early pregnancy and I called my Dr's line at 11pm, he called back and said it was fine. I did experience it like 2-3 nights straight. I'm now 30 weeks, 31 weeks tomorrow with no more of that and a smooth pregnancy
that early you can have some bleeding. don't worry too much till you hear from your dr.
Don't stress too much. It sounds like old blood and that's very normal ☺. Only worry if the blood becomes bright red,followed by cramping. I've had bleeding on and off much like a period since 9wks now I'm 11wks today and had my 1st ob appt and found out I have a sub chronic hemorrhage. I've been freaking out and very stressed but the dr said no worries cuz the hemorrhage is very small and they heal on their own. Thank god. Everything will be okay